Differential type pneumatic piston pump



Sept. 1942 A. BOYNTON 2,296,835

I I DIFFERENTIAL TYPE PNEUMATIC PISTON PUMP Original Filed Jan. 51, 1939 ALEDCANDER BOY N TON,

26 r BY B13146 @w 63 ATTORNEYS Fig.1 Fig. 2.

Patented Sept. 29, 1942 UNITED STATES ATENT OFFlCE DEFFERENTIAL TYPE PNEUMATIC PISTGN PUM Alexander Eoynton, San Antonio, Tex.

19 Claims.

My invention relates to a means for lifting liquids from wells and of propelling liquids through pipe lines by the force of compressed air or gas expanding under or behind a slug of liquid admitted into the eduction tube of a well or into a pipe line by the automatic action of valves which alternately admit a slug of liquid of predetermined weight and then admit under or behind the slug enough compressed air orgas to expel it from the Well or pipe line.

This application is a division of my prior application' Serial No. 253,875, filed January 31, 1939, which matured into Patent 2,248,949, July 15, 1941, and also relates to the subject matter generally disclosed in my co-pending applications Serial Nos. 253,876 and 253,877, also filed January 31, 1939, and of which the latter has matured into Patent 2,262,751, November 18, 1941.

One of the objects of this invention is to provide a pump for lifting liquids from wells by -means of an expanding pneumatic piston, thereby eliminating the expensive, complicated and troublesome cups, plungers, working barrels, sucker rods, jacks, and other unnecessary machinery now generally used to lift liquids from wells.

A further object of this invention is to provide a pneumatic piston pump adapted to use either high or low air or gas pressure for expelling either heavy or light slugs from a well without requiring any change in construction or adjustment of "parts, the device being adapted to automatically regulate the relation between the Weightof the slug to be lifted and the air or gas pressure used 'to lift it. Slugs of diiTerent Weights or lengths may be expelled from wells by means of simply varying the pressure of the air or gas used to lift the slug. By increasing the air or gas pressure, the length or weight of the slug is increased, or vice versa; thereby overcoming the serious difficulty of having to remove the device from the well and of having to change the adjustment so as to expel slugs of different lengths or weights.

A still further object of this invention is to provide means whereby a great number 'of wells varying widely in depth and production each may be produced economically and efiiciently by-compressed -air or gas from one central compressor plant or by gas from any other source simply by regulating the air or-gas pressure supplied to-each well for the purpose of expelling 'oil, Water, or mud fluid therefrom.

Another important object of this invention is to provide a means of lifting liquids from wells,

or slightlycompressed air or gas without allowing any of the air or gas pressure to contact the Well liquids so as to transmit pressure against the producing formation at any time.

The slug of liquid is admitted into the eduction tube of a'well or into a pipe line by means of a valve that controls the admission of liquid thereto (hereinafter referred to as the liquid intake valve) after a valve that controls th admission of compressed air or gas thereto (hereinafter referred to as the'air or gas valve) moves from one seat, referred to as the first seat, and closes upon another seat, referred to as the second seat. The air or gas valve and the liquid intake valve are urged to the only position in which they both are closed by a spring which may Work in conjunction-with a latch; the latching means tending to hold the air or gas valve and the liquid intake valve closed in the first position, and tending to hold the air or gas valve closed'in the second position while the liquid intakevalve is open. The force of the air or gas is utilized to hold the air or gas valve seated upon the second seat while the slug of liquid to be expelled is entering the eduction tube or pipe line through the liquid intake valve.

The weight or back pressure of the slug of liquid thus admitted into the eduction tube or pipe line is utilized to unseat the air or gas valve from the said second seat, and to hold the air orgas valve open intermediate its two seats, while, in that position, the liquid intake Valve cuts oil .the admission of more liquid, until the slug has been expelled; whereupon the air or gas valveagain assumes the closed position upon its second seat with the liquid intake valve open. This cycle is regardless of depth,"by the use of either greatly 55 repeated automatically during the period of operation.

.With the above and other objects in View, this invention has particular relation to certain novel features of construction, operation, and arrangement of parts which manifestly can be changed and combined in different ways within the scope and purpose of this invention.

Other objects and advantages of this invention will be apparent from the following description of the invention which is illustrated in the accompanying drawing in which:

Fig. 1 is a vertical section of an embodiment of the invention;

Fig. 2 is avertical section of a modified form of the construction shown in Fig. 1;

Fig. 3 is a horizontal section on line 3-3, Figs. 1 andZ;

Fig. 4 is a horizontal section on line'4-4, Fig. 1;

Fig. 5 is a horizontal section on line *55, Fig 1;

Fig. 6 is a horizontal section on line 6-6, Fig. 2;

Fig. 7 is a horizontal section on line 1-1, Fig. 2.

Similar characters of reference are employed to designate similar parts throughout the several views.

The invention comprises a connection member 2lA connected in an eduction tube l3 which extends downwardly within a surrounding pressure tube and has hermetic engagement therewith proximate its lower end by means of the lead seal [1, as is well known in the art and as is illustrated in my prior Patents 2,042,583 and 2,104,068.

A connection 58 is threadedly connected to the eduction tube or flow tubing !3 and connects with the upper case nipple 52A which is in turn attached to the air or gas intake connection member 27A. The lower case nipple 52B interconnects the air or gas intake connection member Z'EA and the lead seal carrier nipple 26A which is provided with a check valve and liquid intake governor assembly to be more fully described.

Pressure fluid surrounding the eduction tube 13 and the valve assembly thus generally described enters through the transverse port 21a of the air or gas intake member 27A, passes by way of the passage 27?), the annular space around latch shaft A and contacts the double air or gas valve 23A within the valve seat nipple 29 which contains the spaced opposed seating surfaces Zld and 29a. When the air or gas so admitted reaches a predetermined Pressure the valve 28A, normally held on the seat 2ld by the eXpansiVe force of coil spring 3| and the coacting latch mechanism, moves quickly to engage seat 23a in the nipple 29.

Before the foregoing movement takes place, the liquid intake valve 28B is gripped as shown by the yieldable ring 55, which may be of oilproofed rubber, held in place by the metallic ring 56 pressed into the connection 58 and the screwed-in metallic ring 51, the gripping force against the valve 28B by yieldable member being the well fluid pressure transmitted against the outer surface thereof through the annular space 58a and the horizontal ports 58b. This arrangement of the male and female members of the liquid intake valve results in a leak proof seal against the entrance of well liquid into the eduction tube I3 until the air or gas valve is forced to move from its first position upon the seat 21d to its second position upon the seat 2911. After this movement takes place, the liquid intake valve 28B is open, the air or gas valve travel being enough to raise the valve 25B well above the ring 58. Well liquid then enters the fiow tubing through the check valve assembly comprising the ball check valve 53 which is adapted to close downwardly upon the seat member 54A.

When the weight of the liquid slug so admitted, plus the force of the spring 3|, is equal to the air or gas pressure the air or gas valve will recede from its seat 29a unless this action is delayed by the latch. When the air or gas valve opens, due to the weight or back pressure of the well liquid slug, it will assume position intermediate its two seats all or part of the time until the slug is expelled. If the annular space between the air or gas valve 28A and the nipple 29 be larger than necessary, the rapid input of compressed air or gas under the slug may temporarily cause the liquid intake valve 28B to close or partially close. If this should happen, the valve would open again as soon as the air or gas under the slug had expanded enough to lessen the back pressure to the approximate value thereof at the time when this valve first opened under the slug. Once the slug is expelled from the flow tubing, the air or gas valve again closes upon the seat 29 a. Another slug of well liquid enters, and this cycle automatically repeats.

The check valve seat member 54A is screwed into place as shown. The lower end of this member provides a seat for the coiled liquid intake governor spring 62, the lower end engaging upon the fins Bid at the upper end of the liquid intake governor 6| which fins are urged thereby resiliently toward the top of the seat member 65 upon which they normally seat. The seat member 60 is made in two parts as shown in Fig. 5 for the purpose of assembling upon the liquid intake governor 6|. The seat member 60 may be pressed into place. The purpose of the liquid intake governor is to slow down the entrance of well liquid as it passes through the device, and particularly, as it passes the liquid intake valve 283 in order to prevent undue damage by the abrasive force of sand and other solids frequently contained in well liquids.

In order to prevent slowing down the flowing operation during times when there may be near equality between the pressure of the well liquid and the weight of the slug admitted into the eduction tube, two passages are open for the admission of ,well liquid into the eduction tube, viz: the central drilled passage 61b and annular passage 6lc. At such times of near equality between the pressures above and below the governor 6|, spring 62 will hold the governor 6| in the lower position in order to freely admit well liquid at such time when the slow movement thereof would not damage the device. If, however, the liquid level in the well is very high or if strong gas pressure should be pressing down upon it, the annular passage Blc will be closed at a predetermined difierence between said pressures. Well liquid, therefore, can enter the device only through the central passage Bib at times of high velocities there. The diameter of the central passage Blb should be such that no possible velocity of liquid to be fed into the device by the well will permit the valve 283 to be unduly cut or abraded.

The lower end of the air or gas intake connector member 21A has an externally threaded reduced section to which is attached the latch housing nipple 39 which is closed at its lower end by an externally threaded plug 59. The latch shaft 36A extends downwardly through the axial passage Zlb in the connector 27A and into the latch housing formed by the nipple 39 and the plug 59. A latch assembly within this housing comprises the spring 3| which rests upon the upper end of a ball roof 32 which slidably surrounds the latch shaft 36A and which urges the circularly arranged latch balls 33 downwardly upon the ball floor 34 secured in place upon the latch shaft by means of the lock nut 35 upon the lower end of the latch shaft.

The ball roof 32 and the ball floor 34 are beveled as shown for the obvious purpose of urging the latch balls 33 outwardly by the force of the spring 3|. A latch sleeve 38 may be pressed into the nipple 39. The ball floor 34 and the 110d; hut is provide adjustment 'wherebythe latch rhea held in proper position when the circularly arranged latch balls 33 are urged outwardly rate latching engagement with the ends of the latch sleeve 38. It will be noted also that the annular clearance Z'I'J in the passage '21?) provides a breather space to insure free action of the latch mechanism just described.

obviously the latch sleeve 38 may be filled with oil, "gl-ye'eri'rior the like to lubricate the latch. The longitudinal peripheral openings 38a provide that the lubricant can "circulate freely durtl'fe latch movement's.

Well liquid rising through the check valve assembly within the lewer end of the nipple 5213 l passes through a pluralityo'f liquid passages 210 which by-pas's the pressure fluid inlet ports 21a in the connection member 2lLA.

Fig. 2 shows'an alternative embodiment of the invention. The flow tubing I 3 is threade'dly joined to the connection 58A the lower end of which is joined by threads to the connection 64 to which the case nipple 52A is joined. The air or gas intake member 27B joins together case nipples 52A and 523, the latter being threadedly connected to the lead seal carrier nipple 2613.

The metallic ring '56 is shown pressed into the connection 58A. The yieldable ring 55, which may be of oil proofed rubber, rawhide, or other suitable substance, is held between the 'metallic ring 56 and the upper end of connection 6 as shown. The ports Ma, the annular space 65b, and the opening E ie between members fi l and 58A provide that fluid under pressure leaking past the slide valve 65 will be transmitted central passage through the connection M and i the upper end of the central passage through valve sleeve member '61. The lower end of valve member 65 has a horizontal passage 650 com- :munic'ating with the vertical passages 85b which in turn communicate with the lower horizontal passages 65c for the purpose of transmitting pressure from within the chamber 66a to the inner surface of'the yieldable member 68 which then produces a leak proof barrier between the chambers 66a, and 66b. The combination valve 66 has clearance between it and the inner wall of the chamber within which it is positioned for the purpose of allowing compressed air or gas to flow past it when positioned intermediate its two seats to expel the slug of liquid from the flow tubing, as willbe explained later. This valve is connected threadedly at its lower end to the latch shaft B to which it is locked by the lock nut 69. l

The latch shaft 3613 supports a latch similar to the one shown in my prior Patent 2,010,135. The lower end of the air or gas intake connection member 2113 is circularly beveled for a ball roof as shown at 21f, the bevel being inclined upward to coact with another inwardly inclined bevel of the ball floor 10 to urge the latch balls 33 inwardly toward the shaft 353 by the expansive force of the spring 3'! installed under some compression-and having'its upper seat in :a circular recess in the lowerend of ball floor TE) lower end of the central extension of the member 2133 and is closed at its lower end by the plug 59. A lubricant may be placed within nipple -39 to lubricate the latch. The horizontal passages 21g provide that the lubricant may circ'ulate around the latch mechanism, thereby preventing the latch movement from being impaired by the lubricant. V

The check valve 53 prevents compressed air or gas from escaping from the device into the lower regions of the well. 'The check valve seat member 55B is pressed into the nipple 26B and holds the liquid intake governor 63 in place as shown. The slots 63g. of the liquid intake governor are of restricted area to prevent too rapid inlet of well liquid which might damage "the parts, as was explained for the form of this "invention as shown in Fig. 1.

'In idleness all valves are held normally closed by the spring 31 shown in Fig. 2. Compressed air or gas, when turned into the unshown pressure tubing surrounding the eduction'tubing I3, enters the device through the ports Zla and through theco'mmunicating vertical passage 21b and contacts the lower end of combination valve 86. The latch releases at predetermined pressure under said valve seated upon the seat 21h. The double combination valve 86 then seats with a slam on its upper seat 67a. The passage of compressed air or gas from the pressure tubing into the flow tubing is again prevented by valve 'te, now upon its second seat 67a, but the liquid intake valves 65 and 28D are now open because all valves move as a unit and the travel from the lower to the upper seats of the air or gas valve is such as'to move the lower end of valve 65 abov the laterally inclined circular openings 61b between members M and 6'! which opening communicates with the well liquid via the cored passages 2 1 c and other openings leading to the lower intake-members of the tubing.

The same upward movement opens the valve members 65 and 650. A slug of Well liquid 'is now free to enter the eduction or flow tube l3. When enough well liquid has entered the flow tubing this liquid, aided by the expansive force of spring 3|, will balance the air or gas pressure under the double valve 66 and overcome the latching force. All valves then will move downward.

The latch is adjusted to hold with enough force in the upper position of the valves toclose the slide valve 65 when the latch releases. slight downward movement'that closes the valve '65 does not close the valves 28D and 660. Air or gas therefore is free to pass all valves and expel the slug of liquid from the flow tubing. This expulsion dissipates the back pressure 'above the valves which again causes the combination valve 65 to close upon its upper seat 61: while the liquid intake valves 65 and 28D are open. This cycle automatically repeats during the period of operation, as is apparent.

'It will be noted that, due to the upper =enlarged bore of the sleeve 61 above, the enlargement has open space around it'when the two upper valves 65 and 28D are wide open. When the valves 28D and G6 are closed as shown in Fig. 2 any fluid under pressure that might enter from the well past the slide valve 65 or any air or gas under pressure that might leak past the valve 66 on the seat 21h will exert pressure on the inner sides of the expansive members 68 and 55 through the ports 64a, the annular space 64b, and the open space 640 leading to the yieldable ring 55 and through the horizontal passages 65c, 65d, and 65a leading to the expansible member 68 shown in Fig. 2 as was explained for the similar valve 28B shown in Fig. 1. This construction using a double air or gas valve and a double liquid intake valve in the idle position of the valve insures that well liquid will not flood the flow tubing and the pressure tubing in times when the device is not being operated.

If the flow and pressure tubings should become flooded by well liquid, excessive air or gas pressure would be required to initiate the flowing operation, This construction insures low starting pressure which is one of the important features of the invention.

Particular attention is invited to the valve 65, Fig. 2. It will be noted that this valve will function like new until it is completely worn out, because all wear takes place on the inside while the bearing surface is on the outside. This is true because the path of the well liquid is through openings 651) between partitions 65a. The bearing surface of the valve in the member 6'! is not in the path of the Well liquid. Neither will the bearing surface within member 64 be abraded by foreign substances in the well liquid because this surface is completely shielded by the valve 65 in its upper position, which is the only position in which this valve permits well liquid to enter the eduction tube. It will be further noted that this valve operates to control the admission of well liquid only, while it is open at all times to the passage of compressed air or gas through openings 65b.

It is to be understood that all references to positions such as upper and lower, upward and downward, etc., apply to the device as illustrated in the drawings wherein the normally upper portion of the device is shown uppermost.

While I have shown and described the preferred embodiment of my invention and a modification thereof, it will be understood that the same are illustrated examples only, and are not intended to limit minor variations in the construction and apparent uses of the invention.

The invention claimed is:

1. In a device of the class described, a flow tube including an intake connector, an intake passage therein for a gaseous fluid, additional passages for liquid longitudinally of the connector, said last mentioned passages terminating in radial ports in the intake passage, spaced upper and lower valve seats in the intake passag below said ports, a valve assembly within said intake passage, a valve member movable between said seats, a slide valve adapted to open said ports when said valve member is moved to engage the upper valve seat, valve means intermediate said valve member and slide valve for sealing the passage against movement of fluid downwardly when the valve member is seated upon the lower valve seat, said valves being included in and movable with said assembly, and means for moving the assembly and simultaneously operating said valves.

2. In a device of the class described, a flow tube including an intake connector, an intake passage therein for a gaseous fluid, additional passages for liquid longitudinally of the connector, said last mentioned passages terminating in radial ports in the intake passage, spaced upper and lower valve seats in the intake passage below said ports, a valve assembly within said intake passage, a valve member movable between said seats, a slide valve adapted to open said ports when said valve member is moved to engage the upper valve seat, means on opposite sides of said slide valve for sealing the passage against movement of liquid to the gaseous fluid intake passage and the interior of the flow tube when the valve member is seated upon the lower valve seat, said assembly including said valves and means, and means for moving the assembly to simultaneously operate said valves.

3. In a device of a class described, a flow tube including an intake connector, an intake passage therein for a gaseous fluid, additional passages for liquid longitudinally of the connector, said last mentioned passages terminating in radial ports in the intake passage, spaced upper and lower valve seats in the intake passage below said ports, a valve assembly within said intake passage, a valve member movable between said seats, a slide valve adapted to open said ports when said valve member is moved to engage the upper valve seat, valve means intermediate said valve member and slide valve for sealing the passage against movement of fluid downwardly when the valve member is seated upon the lower valve seat, said means being operable to open the passage as the valve member approaches the upper valve seat, said assembly including said valves and valve means, and means for moving the assembly to simultaneously operate the valves.

4. In a device of the character described, an eduction tube, a connector in said tube, a pressure fluid inlet passage from the exterior to the interior of the connector, a poppet valve alternately engageable upon two opposed seats in the passage, a solid slide valve adapted to close said inlet passage when said poppet valve is engaged upon one of said seats and to open when said poppet valve is engaged upon the other of said seats there being passages for well fluid through said connector past said valves, a sleeve valve adapted to control th flow of well fluid through said last mentioned passages and into the eduction tubing, and a liquid intake valve above said sleeve valve.

5. In a pneumatic piston pump, an eduction tube, a connector in said tube, a pressure fluid inlet passage from the exterior to the interior of the connector, a valve assembly including a double-ended poppet valve engageable upon opposed seats in the inlet passage to control the inflow of pressure fluid, there being passages for well fluid through said connector past said poppet valve, a sleeve valve to control the inflow of well fluid, a third valve between said first two valves, a fourth valve above said sleeve valve, said third and fourth valves being adapted to form a seal in the passage at opposite sides of the sleeve valve, and means for simultaneously operating said valves.

6. In a device of the character described, an eduction tube, a connector in said tube, a pressure fluid inlet passage from the exterior to the interior of the connector, longitudinal openings n the connector for well liquid to by pass the inlet passage, and a valve assembly for controlling the flow of pressure and well fluids, a valve for controlling the inlet of pressure fluid, a second valve for controlling the flow of well liquid, means for sealably closing the passage at opposite sides of the second valve when both of said valves are closed, said assembly including said valves and means, and means for moving the assembly to operate the valves.

7. In a device of the character described, an eduction tube, a connector in said tube, said connector having a transverse inlet for pressure fluid and longitudinal openings for well liquid by-passing said inlet for pressure fluid, an intake passage for the pressure fluid communicating with said transverse inlet and terminating thereabove, a nipple expanding and elongating said passage upwardly, two valve seats in said passage, a valve member having two valves formed upon it in said passage, one of said valves being engageable upon a valve seat upon said connector and the other of said valves being engageable upon a valve seat within said nipple, valve controlled means for alternately admitting pressure fluid and well liquid into said eduction tube, said means being responsive to movements of said valve member, a latch employed in combination with the force of gaseous fluid and well liquid to control the movements of said valve member, and valve control means in combination with means for preventing such pressure fluid from exerting force upon the producing formations of a Well.

8. In a device of the character described, an eduction tube, a connector in said tub-e, said connector having a transverse inlet for pressure fluid and longitudinal openings for well liquid bypassing said inlet for pressure fluid, an intake passage for the pressure fluid communicating with the transverse inlet and terminating thereabove, a nipple expanding and elongating said passage upwardly above said longitudinal openings, two valve seats in said passage, a poppet valve member having two valves formed upon it in said passage, one of said valves being engageable upon one of said seats on said connector and the other of said valves being engageable upon the other of said valve seats within said nipple, valve controlled means for admitting pressure fluid and well liquid into said eduction tube, said means being responsive to movements of said valve member, and a latch employed in combination with the force of gaseous fluid and well liquid to govern the movements of said control means.

9. In a device of the class described, a flow tube including an intake connector, an intake passage therein for a gaseous fluid, additional passages for liquid longitudinally of the connector, said last mentioned passages terminating in radial ports in the intake passage, spaced upper and lower valve seats in the intake passage below said ports, a valve assembly within said intake passage, a valve member movable between said seats, a slide valve adapted to open said ports when said valve member is moved to engage the upper valve seat, valve means intermediate said valve member and slide valve and responsive to fluid pressure above said valve member to seal the passage against movement of fluid downwardly when the valve member is seated upon the lower valve seat, said valve assembly including and adapted to simultaneously move said valves and means, and means for moving said assembly to operate the valves.

10. In a device of the class described, a flow tube including an intake connector, an intake passage therein for a gaseous fluid, additional passages for liquid longitudinally of the connector, said last mentioned passages terminating in radial ports in the intake passage, spaced upper and lower valve seats in the intake passage below said ports, a valve assembly within said in- 

